21719233 has 8 divisors (see below), whose sum is σ = 22359680. Its totient is φ = 21088080.

The previous prime is 21719219. The next prime is 21719237. The reversal of 21719233 is 33291712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21719233 - 2⁹ = 21718721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21719237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2566 + ... + 7072.

It is an arithmetic number, because the mean of its divisors is an integer number (2794960).

Almost surely, 2^21719233 is an apocalyptic number.

It is an amenable number.

21719233 is a deficient number, since it is larger than the sum of its proper divisors (640447).

21719233 is an equidigital number, since it uses as much as digits as its factorization.

21719233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4647.

The product of its digits is 2268, while the sum is 28.

The square root of 21719233 is about 4660.3897905647. The cubic root of 21719233 is about 279.0068257131.

It can be divided in two parts, 21719 and 233, that added together give a cube (21952 = 28³).

The spelling of 21719233 in words is "twenty-one million, seven hundred nineteen thousand, two hundred thirty-three".